JPS6242798Y2 - - Google Patents

Description

[Detailed description of the device] This device circulates constantly aerated wastewater from the contact aeration chamber to the sedimentation separation chamber using an air lift pump, making the sedimentation separation chamber almost aerobic and preventing the generation of odors and scum. Concerning improvements to separate contact aeration type septic tanks.

Conventionally, separate contact aeration type septic tanks have been proposed in which sewage is subjected to sedimentation treatment in a sedimentation separation chamber and then contact aeration treatment, but one of the problems with this method is that the separated floating sludge is returned to the sedimentation separation chamber. It is. To solve this problem, there are natural return using a communication port between the sedimentation separation chamber and the aeration chamber, and intermittent return using a return air lift.

In particular, the return method using an air lift has the advantage of being able to return the sludge reliably, but on the other hand, it takes a long time to return the sludge, and during inspections, air lift pumps are usually placed on one floor by means such as switching valves. Since the drive is then sent back, it is difficult to readjust it afterwards, and if there is even a slight delay in inspection, there are drawbacks such as the SS being discharged.

This invention solves the above-mentioned drawbacks, and uses a communication port that opens into the water near the water surface in the partition between the sedimentation separation chamber and the contact aeration chamber, and an air lift to constantly circulate aerated wastewater, etc. to the sedimentation separation chamber. It is an object of the present invention to provide a separation contact aeration type septic tank that makes the sedimentation separation chamber almost aerobic, prevents odor, scum, etc., and does not require valve adjustment.

An embodiment of this invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, the inside of the tank body 1 made of FRP or the like includes a partition plate 2,
It is partitioned into a precipitation separation chamber 4, a contact aeration chamber 5, and a precipitation chamber 6 by a separator 3 that communicates downward. At one end of the tank body 1, there is an inflow pipe 8 connected vertically to an inflow vertical pipe 7 with open upper and lower ends at the inflow end in the sedimentation separation chamber 4; A wastewater discharge pipe 10 is provided in communication with a disinfection chamber 9 provided in the chamber 6, respectively.

On the partition plate 2 side of the sedimentation separation chamber 4, in order to return the separated sludge etc. from the contact aeration chamber 5 to the sedimentation separation chamber 4, there are vertically arranged holes surrounding the communication port 2a bored in the partition plate 2. An elongated advection pipe 11 is provided to introduce the wastewater after precipitation separation into the contact aeration chamber 5.

The inside of the contact aeration chamber 5 is partitioned into an aeration stirring chamber 12 near the communication port 2a and a contact material 13 filled around this aeration stirring chamber 12. Below this contact material 13 is a backwash pipe 14. is located.
Further, the aeration stirring chamber 12 is provided with an aeration pipe 15 disposed at a lower portion thereof, and an air lift pipe (air lift pump) 16 for circulating aerated wastewater or the like. One end of this air lift pipe 16 is opened at the lower end of the aeration stirring chamber 12, and the other end communicates with the inflow vertical pipe 7 in the precipitation separation chamber 4 as a circulating water pipe 16a. As shown in FIGS. 1 to 3, in a substantially horizontal portion of the circulating water pipe 16a and directly below the inspection port 1a of the sedimentation separation chamber 4, there is a monitoring window 17 formed of a notch for checking the flow state. is provided.

As shown in FIG. 4, the backwash pipe 14, air diffuser pipe 15 and air lift pipe 16 are connected to an air pipe (connection pipe) 18 from one blower, and are connected to the tank main body 1.
It is branched off at a place where it is easy to work, such as directly under the inspection opening 1a inside or outside of the.

Then, the air pipe 18a to the backwash pipe 14, the air pipe 18b to the air diffuser pipe 15, and the air lift pipe 16, 1
Valves 19 and 20 are provided on at least one of the air pipes 8c, and the backwash pipe 14 is placed shallower than the air discharge ends of the aeration pipe 15 and the air lift pipe 16.

A disinfection chamber 9 having an overflow weir 21 is provided above the contact aeration chamber 5 and the precipitation chamber 6 separated by the separator 3, and a discharge pipe 10 is connected to the disinfection chamber 9.

Next, the function and effect of this invention will be explained.

The wastewater introduced into the tank body 1 is discharged from the discharge pipe 10 after undergoing precipitation separation, contact aeration, precipitation, and disinfection treatment. Under normal conditions, the valve 19 of the backwash pipe 14 is closed, and the other valve 20 is used to adjust the ratio of the amount of air supplied to the diffuser and air lift. Circulation of aerated sewage and return of stripped sewage through the communication port 2a are carried out continuously.

Here, when the valve 19 of the backwash pipe 14 is opened during inspection, the backwash pipe 14 is located at a shallower position than the aeration pipe 15 and the air lift pipe 16, so the backwash pipe 14 is opened without any adjustment of the valve 20. Aeration is performed only through the washing pipe 14, and the contact material 13 is backwashed and washed.

After that, if you close the valve 20 of the backwash pipe 14,
Aeration and circulation resume as before. At this time, since the ratio between air diffusion and air lift was not adjusted during backwashing, operation could be resumed as is, and the circulation status could be confirmed through the monitoring window 17 below the inspection port 1a.

As mentioned above, since the circulation of aerated sewage etc. by the air lift and the return of the peeled sludge through the communication port 2a are always carried out, most of the inside of the sedimentation separation chamber 4 can be kept aerobic. It has the following effects.

Since the sedimentation separation chamber is kept aerobic, odor and scum generation inside the room can be suppressed.

Since the interior of the sedimentation separation chamber is diluted and the concentration is low, even if there is a sudden inflow, highly concentrated wastewater will not flow into the contact aeration chamber, and the shock of inflow can be alleviated.

Aerobic treatment is also carried out in the sedimentation separation chamber.
Overall, the amount of sludge produced is reduced.

Most of what settles in the precipitation separation chamber is hard-to-decompose (eg, fiber) solids.

In particular, in combined treatment septic tanks that also receive gray water, etc., the peak flow rate is very large, and if the supernatant concentration in the sedimentation separation chamber (the water quality is almost the same as the effluent water) is kept low, the quality of the effluent water will not deteriorate. .

FIG. 5 shows another embodiment, in which the sedimentation separation chamber 4 is partitioned by a separator 2 communicating with the lower part to form a secondary sedimentation separation chamber 4a, and the circulating water pipe 16a of the air lift pipe 16 is connected to the secondary sedimentation separation chamber 4a. This is a separate contact aeration type septic tank located above the chamber 4a.

According to the septic tank of this embodiment, aerated sewage, etc. in the contact aeration chamber 5 is constantly circulated to the secondary precipitation separation chamber 4a by the action of the air lift pump. Therefore, the secondary precipitation separation chamber 4a is kept aerobic, and the water quality here is almost the same as in the contact aeration chamber 5.

In a general septic tank, at the time of peak inflow, a large amount of supernatant liquid from the sedimentation chamber with poor water quality flows into the aeration chamber, increasing the load and deteriorating the water quality, but in this embodiment, the secondary sedimentation chamber 4a is provided as a backup. It becomes an oxidation chamber, and the quality of the wastewater flowing into the contact aeration chamber 5 at the time of peak inflow improves, and the load on the contact aeration chamber 5 is reduced. The capacity of the secondary precipitation separation chamber 4a may be set in accordance with the peak inflow amount, such as the capacity of a bath drain in the case of household combined processing, for example.

What is shown in FIG. 6 is still another embodiment,
The precipitation separation chamber is filled with contact materials 19 and 20.

The sedimentation separation chamber is divided into an anaerobic chamber 4 by a partition plate 18.
It is divided into an aerobic chamber 4a and an aerobic chamber 4a. A passage 4c is provided along this partition plate 18 to guide the airlift circulating water downward. Also, this passage 4
C also serves as an inlet for a vacuum hose during cleaning, and an overflow channel that guides wastewater to the lower part of the aerobic chamber when the water level in the anaerobic chamber 4b rises abnormally. The anaerobic chamber 4b and the aerobic chamber 4a are filled with contact materials 19 and 20, respectively.

In this embodiment, the inflowing wastewater first flows into the anaerobic chamber 4b.
It undergoes precipitation separation and anaerobic decomposition treatment. After passing through the material 19, it is mixed with the circulating water from the communication path 4c, and the material 20 in the aerobic chamber 4A is mixed with the circulating water from the communication path 4c.
and undergo aerobic treatment. The wastewater that has undergone aerobic treatment flows into the contact aeration chamber 5 and is treated in the same manner as in the other embodiments.

In this embodiment, since the aerobic chamber 4a is kept aerobic by the circulating water, the quality of the water flowing into the contact air chamber 5 is maintained very well. It is very effective because it is also treated with airborne microorganisms. Furthermore, since anaerobic decomposition processing is performed by the anaerobic bacteria held in the material 19 in the anaerobic chamber 4b, the amount of sludge generated is also small. In addition, since the material acts as a resistance to the flow, there is no short circuit, and the inflow shock can be alleviated.

It should be noted that one of the materials 19 and 20 may be omitted, or the materials may be placed in the undivided sedimentation chamber shown in FIG.

As described above, according to the separated contact aeration type septic tank of this invention, an air lift pump for circulating water is installed in the contact aeration chamber, and this air lift pump constantly circulates water to the sedimentation separation chamber, so that sedimentation is separated. It has the effect of making the room almost aerobic and preventing the generation of odors and scum.

[Brief explanation of the drawing]

Figure 1 is a longitudinal sectional view of one embodiment of this invention;
The figure is a sectional view taken along the line A-A in Figure 1, Figure 3 is a perspective view of the monitoring window of the return pipe, Figure 4 is an explanatory diagram of the blower piping, and Figures 5 and 6 are of other embodiments. A vertical cross-sectional view is shown. 1...tank body, 4...precipitation separation chamber, 5...contact aeration chamber, 12...contact stirring chamber, 13...contact material, 14...backwash pipe, 15...aeration chamber, 16...
Air lift pipe (air lift pump), 18... Connection piping, 19, 20... Valve.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A precipitation separation chamber and a contact aeration chamber partitioned within the tank body, an aeration stirring chamber partitioned within the contact aeration chamber, and the aeration stirring chamber and the precipitation separation described above. A communication port is provided in the partition of the chamber and opens underwater near the water surface; an aeration pipe is placed in the aeration stirring chamber to aerate the waste water; A separation contact aeration type septic tank equipped with an air lift pump for forcibly circulating received sewage etc. to the sedimentation separation chamber. (2) The air lift pump is characterized in that it has a horizontal circulation water pipe that circulates the sewage, etc. that has been aerated in the contact aeration chamber to the sedimentation separation chamber, and that this circulation water pipe is provided with a monitoring window. A separate contact aeration type septic tank according to claim 1 of the utility model.